ISIS Calls The Killer A 'Soldier' of the group

ABOVE VIDEO: There are at least six American casualties from Thursday night’s attack on France. Two of them, a father and his 11-year-old son, are confirmed dead. One is still missing. Omar Villafranca has more. (CBS Video)

(CBS NEWS) – The Islamic State of Iraq and Syria, or ISIS, on Saturday claimed the Tunisian man who barreled his truck into a crowd in the French resort city of Nice was a “soldier” of the group, the first claim of credit for an attack that has claimed 84 lives and wounded more than 200 people.

The claim – circulated on social media by a news outlet affiliated with the group – didn’t name Mohamed Lahouaiej Bouhlel, the 31-year-old Tunisian who authorities say was behind the wheel as his truck crashed into a crowd of revelers at a fireworks display on Thursday.

But the statement quoting a security member of the group said the man was following calls from ISIS to target nationals of countries fighting it.

The nature and scope of Bouhlel’s relationship with ISIS hasn’t been established. It’s also unclear whether or not he was acting alone. The Paris prosecutor’s office said Saturday that five people are in custody following the attack.